In many filtration processes today membranes are utilized to filter various components of fluid systems. For example, membranes are used to separate gas components from each other in gaseous streams containing multiple gases, to separate various dissolved components in liquid solutions from each other and to selectively permit certain ions in a solution to pass across a membrane while blocking others. Membranes are also utilized to a great extent to immobilize proteins, enzymes and cells. The enzymes, so immobilized are used as catalysts to increase reaction rates or to convert materials in solution from one form to another. Membranes are also utilized in various applications today to trap or immobilize living cells within a substrate forming the membrane.
In general, membranes of various types have been employed for these purposes. In the electrolysis field, for example, polymer sheet membranes which are selectively permeable to alkali metal ions are utilized. Porous glass beads have also been employed in many processes for the purpose of immobilizing enzymes for use in other chemical processes. Organic fibers have also been utilized in many applications, for example, the dialysis of blood. These organic fibers have been utilized both in the hollow and porous state where the material to be purified, in this case blood, is passed through a hollow organic fiber and is purified by enriching it in oxygen and depleting it of waste materials through the pores.
Inorganic materials are particularly interesting for membrane applications since they are, generally speaking, inert and depending on composition, alkali or acid resistant. These properties render such inorganic materials useful in purification systems that are acidic or alkaline. Further, their inertness renders such inorganic materials useful in cell, protein and enzyme immobilization since they are non-reactive to these substances and also to contaminants such as microorganisms that might be present in solutions being treated. Inorganic substances further can be readily cleaned without suffering severe damage during cleaning and sterilization, whereas many organic substances cannot be cleaned using normal cleaning materials such as calcium hypochlorite solutions. Interest in inorganic substrates in the form of hollow glasses which are porous is demonstrated by an article in "The Journal of Material Science" (11), 1976 at pages 1187-1199 by P. W. McMillan and C. E. Matthews. The recent U.S. Pat. No. 4,042,359 also shows a device made of porous glass tubes. These devices use individual tubes in what appears to be limited capacity reactors since the tubes are separated from each other with each tube restrained at each end. A need, therefore, exists for inorganic substrates that can be effectively utilized in reverse osmosis, ultrafiltration, enzyme, protein and cell immobilization and other like processes in a commercial reactor to provide a large number of porous glass fibers for use in the process being conducted.
Applicants, by virtue of the instant invention, have supplied this need by providing novel fiber glass containing cartridges and reactors which can be effectively utilized for separation and immobilization procedures. The separation or immobilization units (hereinafter referred to as reactors) can be tailored for ultrafiltration, reverse osmosis and microfiltration, as well as for for enzyme, protein and cell immobilization. The cartridges and reactors are compact and designed to carry large quantities of glass fibers in a small cross-sectional area. They are also easily adapted to cleaning and the cartridges can be treated prior to insertion in a reactor to provide fibers having the desired physical characteristics for the particular use to which they will be put.